1. Field of the Invention
The present invention relates to the field of component based user applications and more particularly to the assembly of different components to produce a component based user application.
2. Description of the Related Art
Component based user applications address the rigid nature of unitary, consolidated applications which are programmed to support a particular application need without providing substantial flexibility. In the unitary, consolidated application, little can be done if the particular application needs change. By comparison, in component based computing, different components provide atomic elements of application functionality. Individual components can be combined with other components to dynamically assemble an application which provides a specific type of functionality to flexibly support a particular application need, even as the application needs change. Examples of component based computing implementations include collaborative computing applications and portal computing environments.
Portal frameworks support a component based model for building user facing applications. Portal applications represent assemblies of user-facing components which can be combined in different ways to produce different applications. Portlets are the visibly active, user-facing components included as part of portal pages. Similar to the graphical windows paradigm of windowing operating systems, each portlet in a portal occupies a portion of the portal page through which the portlet can display associated content from a portlet channel. The prototypical portlet can be implemented as a server-side script executed through a portal server.
Portal servers are computer programs which facilitate the distribution of portal based Web sites on the public Internet or a private intranet. Importantly, it will be recognized by one of ordinary skill in the art that the signature characteristic of all conventional portal servers can include the aggregation of content from several portlet applications within a single distributable page in a uniform manner. To that end, each portlet application within the portal page can be represented by a portlet user interface distributed by the portal server to requesting client computing devices.
Cooperative portlets subscribe to a model for declaring, publishing and sharing information with one another using a property broker. Portlets can subscribe to the broker by publishing typed data items or properties that can be shared by the portlet, either as a provider or as a recipient. Generally, a portlet that provides a property is referred to as a source portlet, a portlet that receives a property is referred to as a target portlet, the properties published by the source portlet are referred to as output properties, and the properties that are received by a target portlet are referred to as input properties.
Properties can be exchanged among portlets through a persistent connection referred to as a wire. Using the wire, property transfers can be effectuated between connected portlets. At runtime, a property broker can match the data type of output properties from a source portlet with the data type of input properties from one or more target portlets coupled to the source portlet over separate wires. If a match is determined, the portlets are capable of sharing the property. The actual transfer of the property over the wire can be initiated through the use of a portlet wiring tool, or by establishing a click-to-action event for the source portlet as it is known in the art.
It will be apparent to the skilled artisan, then, that cooperatively interacting component based applications can be assembled through the selective wiring of different, selected components. Determining how components can cooperate with one another in a meaningful way, however, can be challenging. Furthermore, selecting an optimal combination of components for wiring also can be challenging. Finally, selecting an optimal wiring configuration for selected components can be even yet further challenging. Nevertheless, at present, selecting components for wiring is a purely manual exercise, rife with inefficiencies.